• Nuclear Engineering and Technology
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• 제54권11호
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• pp.4030-4048
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• 2022

In this study, road transportation tests were conducted with surrogate fuel assemblies under normal conditions of transport to evaluate the vibration and shock load characteristics of spent nuclear fuel (SNF). The overall test data analysis was conducted based on the measured acceleration and strain data obtained from the speed bump, lane-change, deceleration, obstacle avoidance, and circular tests. Furthermore, representative shock response spectrums and power spectral densities of each test mode were acquired. Amplification or attenuation characteristics were investigated according to the load transfer path. The load attenuated significantly as it transferred from the trailer to the cask. By contrast, the load amplified as it transferred from the cask to the surrogate SNF assembly. The fuel loading location on the cask disk assembly did not exhibit a significant influence on the strain measured from the fuel rods. The principal strain was in the vertical direction, and relatively large strain values were obtained in spans with large spacing between spacer grids. The influence of the lateral location of fuel rods was also investigated. The fuel rods located at the side exhibited relatively large strain values than those located at the center. Based on the strain data obtained from the test results, a hypothetical road transportation scenario was established. A fatigue evaluation of the SNF rod was performed based on this scenario. The evaluation results indicate that no fatigue damage occurred on the fuel rods.

• Steel and Composite Structures
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• 제47권4호
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• pp.467-488
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• 2023

Seismic retrofit of an existing steel-reinforced concrete hospital building that features innovative use of a continuous energy-dissipative steel column (CEDC) system is presented in this paper. The special system has been adopted to provide an efficient solution taking into account the difficulties of applying traditional intervention techniques to minimize the impact on architectural functionality and avoid the loss of building function and evacuation during the retrofit implementation. The lateral stiffness and strength of the CEDC system were defined based on the geometric and mechanical properties of the steel strip dampers. The hysteretic behavior under cyclic loadings was defined using a simplified numerical model. Its effectiveness was validated by comparing the results of full-scale experimental data available from the literature. All the main design considerations of the retrofitting plan are described in detail. The effectiveness of the proposed retrofitting system was demonstrated by nonlinear time-history analyses under different sets of earthquake-strong ground motions. The analysis results show that the CEDC system is effective in controlling the deformation pattern and significantly reducing damage to the existing structure during major earthquakes.

• Earthquakes and Structures
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• 제24권6호
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• pp.393-404
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• 2023

This paper presents the application of hybrid-simulation-based adapter elements for the non-linear two-scale analysis of reinforced concrete frames with masonry infills under seismic-like demands. The approach provides communication and distribution of the computations carried out by two or more remote or locally distributed numerical models connected through the OpenFresco Framework. The modeling consists of a global analysis formed by macro-elements to represent frames and walls, and to reduce global degrees of freedom, portions of the structure that require advanced analysis are substituted by experimental elements and dimensional couplings acting as interfaces with their respective sub-assemblies. The local sub-assemblies are modeled by solid finite elements where the non-linear behavior of concrete matrix and masonry infill adopt a continuum damage representation and the reinforcement steel a discrete one, the conditions at interfaces between concrete and masonry are considered through a contact model. The methodology is illustrated through the analysis of a frame-wall system subjected to lateral loads comparing the results of using macro-elements, finite element model and experimental observations. Finally, to further assess and validate the methodology proposed, the paper presents the pushover analysis of two more complex structures applying both modeling scales to obtain their corresponding capacity curves.

• Structural Engineering and Mechanics
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• 제88권5호
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• pp.419-437
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• 2023

The use of reinforced concrete (RC) shear walls (SW) as an efficient lateral load-carrying system has gained recent attention. However, creating openings in RC shear walls is unavoidable due to architectural requirements. This reduces the walls' strength and stiffness, resulting in the development of wall piers. In this study, the cyclic behavior of RC shear walls with openings, reinforced with carbon fiber reinforced polymer (CFRP) sheets in various patterns, was numerically investigated. Finite element analysis (FEA) using ABAQUS software was employed. Additionally, the retrofitting of sub-standard buildings (5, 10, and 15-story structures) designed based on the old and new versions of the Iranian Code of Practice for Seismic-Resistant Structures was evaluated. Nonlinear static analyses, specifically pushover analyses, were conducted on the structures. The best pattern of CFRP wrapping was determined and utilized for retrofitting the sub-standard structures. Various structural parameters, such as load-carrying capacity, ductility, stress contours, and tension damage contours, were compared to assess the efficiency of the retrofit solution. The results indicated that the load-carrying capacity of the sub-standard structures was lower than that of standard ones by 57%, 69%, and 67% for 5, 10, and 15-story buildings, respectively. However, the retrofit solution utilizing CFRP showed promising results, enhancing the capacity by 10-25%. The retrofitted structures demonstrated increased yield strength, ultimate strength, and ductility through CFRP wrapping and effectively prevented wall slipping.

• Wind and Structures
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• 제38권6호
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• pp.445-459
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• 2024

To model the aeroelasticity in vortex-induced vibrations (VIV) of slender tubular towers, this paper presents an approach where the aerodynamic damping distribution along the height of the structure is calculated not only as a function of the normalized lateral oscillation but also considering the local incoming wind velocity ratio to the critical velocity (velocity ratio). The three-dimensionality of aerodynamic damping depending on the tower's displacement and the velocity ratio has been observed in recent studies. A contour map model of aerodynamic damping is generated based on the forced vibration tests. A sectional calculation procedure based on the spectral method is developed by defining the aerodynamic damping locally at each increment of height. The proposed contour map model of aerodynamic damping and the sectional calculation procedure are validated with full-scale measurement data sets of a rotorless wind turbine tower, where good agreement between the prediction and measured values is obtained. The prediction of cross-wind response of the wind turbine tower is performed over a range of wind speeds which allows the estimation of resulting fatigue damage. The proposed model gives more realistic prediction in comparison to the approach included in current standards.

• Anatomy and Cell Biology
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• 제57권1호
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• pp.18-24
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• 2024

The origin and distribution of median nerve varies among the different individuals. The median nerve variations in axillary region were reported by many authors previously. Understanding of these variations is especially necessary for clinicians to prevent iatrogenic nerve damage. The current work aimed to evaluate the possible anatomical variations of median nerve in the axillary region in a sample of the Iranian cadavers (Shiraz, Fars). We dissected 26 upper limbs from 13 male cadavers to investigate the different variations of median and musculocutaneous nerves according to Venieratos and Anagnostopoulou classification. In 23.07% of specimens (n=6), the medial root united with 2 lateral roots and formed the median nerve proximal to the coracobrachialis muscle. In one case, a communicating branch separated from the musculocutaneous nerve distal to the coracobrachialis and connected to the median nerve in upper arm. Our results suggest that there are anatomical variations of the median nerve in terms of its origin and its communication with the musculocutaneous nerve in the population of southern Iran. The anatomical knowledge of the median nerve variations is important for clinicians to improve patient health outcome. Theses variations of the median nerve should be considered during surgical procedures of the axillary region and nerve block of the infra clavicular part of the brachial plexus.

• Structural Engineering and Mechanics
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• 제91권3호
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• pp.279-289
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• 2024

The purpose of this study is to represent a useful alternative for the preliminary seismic vulnerability assessment of existing reinforced concrete buildings by introducing a statistical approach employing the binary logistic regression technique. Two different predictive statistical models, namely full and reduced models, were generated utilizing building characteristics obtained from the damage database compiled after 1999 Düzce earthquake. Among the inspected building parameters, number of stories, overhang ratio, priority index, soft story index, normalized redundancy ratio and normalized lateral stiffness index were specifically selected as the predictor variables for vulnerability classification. As a result, normalized redundancy ratio and soft story index were identified as the most significant predictors affecting seismic vulnerability in terms of life safety performance level. In conclusion, it is revealed that both models are capable of classifying the set of buildings being severely damaged or collapsed with a balanced accuracy of 73%, hence, both are able to filter out high-priority buildings for life safety performance assessment. Thus, in this study, having the same high accuracy as the full model, the reduced model using fewer predictors is proposed as a simple and viable classifier for determining life safety levels of reinforced concrete buildings in the preliminary seismic risk assessment.

• Archives of Reconstructive Microsurgery
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• 제5권1호
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• pp.24-34
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• 1996

There are many kinds of free flaps for management of extensive soft tissue defect of extremities in orthopaedic field. Free vascularized scapular flap is one of the most useful and relatively easy to application. This flap has been utilize clinically from early eighties by many microsurgical pioneers. Authors performed 102 cases of this flap from 1984 to 1995. We have to consider about the surgical anatomy of the flap, technique of the donor harvesting procedures, vascular varieties and anatomical abnormalities and success rate and the weak points of the procedure. This flap nourished by cutaneous branches from circumflex scapular vessels emerges from the lateral aspect of the subscapular artery 2.5-5cm from its lateral origin passing through the triangular space(bounded by subscapularis, teres minor, teres major, long head of triceps). The terminal cutaneous branch runs posteriorly around the lateral border of the scapular and divided into two major branches, those transeverse horizontally and obliquely to the fascial plane of overlying skin of the scapular body. We can utilize these arteries for scapular and parascapular flap. The vascular pedicle ranged from 5 to 10 cm long depends on the dissection, usually two venae comitantes accompanied circumflex scapular artery and its major branches. The diameter of the circumflex scapular artery is more than 1mm in adult, rare vascular variation. Surgical techniques : The scapular flap can be dissected conveniently with prone or lateral decubitus position, prone position is more easier in my experience. There are two kinds of surgical approaches, most of the surgeon prefer elevation of the flap from its outer border towards its base which known easier and quicker, but I prefer elevation of the flap from its outer border because of the lowering the possibilities of damage to vasculature in the flap itself which runs just underneath the subcutaneous tissue of the flap and provide more quicker elevation of the flap with blunt finger dissection after secure pedicle dissection and confirmed the course from the base of the pedicle. There are minimal donor site morbidity with direct skin closure if the flap size is not so larger than 10cm width. This flap has versatility in the design of the flap shape and size, if we need more longer and larger one, we can use parascapular flap or both. Even more, the flap can be used with latissimus dorsi musculocutaneous flap and serratus anterior flap which have common vascular pedicle from subscapular artery, some instance can combined with osteocutaneous flap if we include the lateral border of the scapular bone or parts of the ribs with serratus anterior. The most important shortcoming of the scapular free flap is non sensating, there are no reasonable sensory nerves to the flap to anastomose with recipient site nerve. Results : Among our 102 cases, overall success rate was 89%, most of the causes of the failure was recipient site vascular problems such as damaged recipient arterial conditions, and there were two cases of vascular anomalies in our series. Patients ages from 3 years old to 62 years old. Six cases of combined flap with latissimus dorsi, 4 cases of osteocutaneous flap for bone reconstruction, 62 parascapular flap was performed - we prefer parascapular flap to scapular. Statistical analysis of the size of the flap has less meaningful because of the flap has great versatility in size. In the length of the pedicle depends on the recipient site condition, we can adjust the pedicle length. The longest vascular pedicle was 14 cm in length from the axillary artery to the enter point cutaneous tissue. In conclusion, scapular free flap is one of the most useful modalities to manage the large intractable soft tissue defect. It has almost constant vascular pedicle with rare anatomical variation, easy to dissect great versatility in size and shape, low donor morbidity, thin and hairless skin.

• 한국잠사곤충학회지
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• 제37권2호
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• pp.99-108
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• 1995

붕소 결핍이 식물의 뿌리 발육에 큰 영향을 미치고 있으며, 특히 붕소가 결핍하면 식물체의 내동성 물질로 알려진 당, 가용성 단백질, RNA, proline 및 인지질 등이 감소하기 대문에 붕소와 뽕나무의 뿌리 발육 및 내동성과 깊은 관계가 있을 것으로 예상하고 이에 대한 실험을 실시하여 다음과 같은 결과를 얻었다. 붕소를 주지 않은 뽕나무의 가지는 50cm 가량 밖에 자라지 않았으며, 붕소를 준 뽕나무는 190cm 이상 자랐다. 붕소를 주지 않은 뽕나무의 가지에 measles 현상이 보였으며 잎의 엽맥은 necrosis현상이 심하였다. 붕소를 주지 않은 뽕나무는 식재 초기에 새 뿌리가 나오다가 70일 후 부터는 새 뿌리와 묵은 뿌리 모두 갈색으로 변하였으며, 붕소시용 뽕나무의 뿌리는 새 뿌리가 왕성하게 발육하였다. 붕소를 주다가 붕소를 주지 않으면 3일 후부터 새 뿌리가 갈색으로 변하였으며, 붕소를 주지 않다가 붕소를 시용하면 2일 후부터 새 뿌리가 나기 시작해서 이것이 왕성하게 자랐다. 고농도 붕소 영양액(0.5ppm)으로 키운 뽕나무의 잎과 줄기 피충부에는 저농도 붕소 영양액(0.01ppm)으로 키운 뽕나무의 잎과 줄기 피충부에서 보다 붕소함량이 많았다. 고농도 붕소 영양액(0.5ppm)으로 키운 뽕나무의 잎과 줄기 피층부에는 저농도 붕소 영양액(0.01ppm)으로 키운 것보다 인지질, 단백질, 당, RNA 및 proline 함량이 많았다. 뽕가지를 -15$^{\circ}C$에서 24시간 처리한 결과 붕소를 준 뽕나무는 정상적으로 발아 하였는데, 붕소를 주다가 주지 않은 뽕나무와 처음부터 붕소를 주지 않은 뽕나무는 전혀 발아가 되지 않았다. 이상의 결과로 보아 붕소는 뽕나무의 뿌리 발육에 지대한 영향을 미치며 나아가서는 뽕나무의 내동성과도 관계가 있음을 알 수 있었다.

• 한국응용곤충학회지
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• 제38권2호
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• pp.157-164
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• 1999

먼지응애류인 벼먼지응애(신칭, Steneotarsonemus spinki Smiely 1967)는 쌀생산국인 태국, 필리핀, 중국, 대만 등에서 쌀의 중요한 해충이다. S. spinki가 국내에서 처음으로 환경조절온실에서 재배중인 쌀에서 발견되었다. 응애 피해를 입은 쌀은 이삭에서 기형을 나타내었으며 잎집내부 표면의 갈변증상, 쌀알의 표면 갈변증상 등을 나타내었다. S. spinki암컷의 체장은 263.0$\mu\textrm{m}$(246.5~$284.6\pm$12.2), 체폭은$ 92.4\mu\textrm{m}$(79.5~$104.9\pm$7.6)였으며 전체적인 모양은 난형으로 중앙부위가 가장 폭이 넓었다. 채색은 연한 황색이었다. 다리는 잘 발달되어 있었으며 암컷 제4각 끝은 채찍모양의 강모로 이루어진 전형적인 먼지응애류의 특징을 가지고 있었다. 수컷 체장은 196.5$\mu\textrm{m}$(176.5~222.8$\pm$15.8), 체폭은 109.3$\mu\textrm{m}$ 98.6~$117.7\pm$6.4)였으며 전체적인 모양은 길쭉하고 전동체부 중앙부가 가장 체폭이 넓었다. 내돌기 III은 내돌기 IV보다 전방으로 신장되어 있었다. 제4각퇴절은 커다란 안쪽귀가 발달되어 있었으며 안쪽 및 바깥쪽 강모는 같은 길이로 짧게 잘 발달되어 있었다. 부절 발톱은 강하고 복부쪽으로 굽어 있었다.